1. Field of the Invention
The present invention relates generally to a parallel computer system and, more particularly, to a parallel computer system, including a one-to-one communication network, for actualizing barrier synchronization through this communication network.
2. Description of the Related Art
In a parallel computer system, a plurality of computer nodes (which are also simply called "nodes") execute arithmetic processes in parallel. Each computer node, if the necessity arises, performs communications with other communication nodes via a communication network connected to all the computer nodes, thereby acquiring data held by other computer nodes and continuing the arithmetic process by use of these pieces of data. In such a parallel computer system, each computer node is required to wait for the acquisition of the data till the data needed by the computer node itself are calculated by other computer nodes. Further, the computer node that holds the data needed by other computer nodes is not allowed to execute an arithmetic process to update the same data until the relevant other computer nodes refer to the data.
If a multiplicity of computer nodes must effect such cooperative operations, it is practiced that synchronization known as barrier synchronization is taken.
The prior art parallel computer system involves the use of a barrier synchronization-only network based on one or a plurality of physical tree structures. Consequently, there is a problem in which the computer nodes participating in the barrier synchronization can not be arbitrarily selected. Moreover, a number of settable synchronizing processes is also unequivocally determined depending on a configuration of the barrier synchronization-only network.